Process and apparatus for texturizing yarn

ABSTRACT

Multiple ends of continuous multifilament yarns are texturized within a pressure applying zone formed by confronting surfaces of a moving belt and a rotating heated roll with said confronting surfaces moving in the same direction. The yarns are arranged in spaced side-by-side relationship and fed at a speed greater than that of the moving belt into contact with the heated roll at a point upstream from the pressure applying zone, the peripheral speed of the heated roll being at least 1.4 times that of the moving belt. The filaments of the yarns are differentially shrunk and then carried into the pressure applying zone, i.e., between the rotating roll and the moving belt. The surface of the moving belt has a greater gripping power on the multifilament yarns than the heated roll surface, whereby the speed of the multifilament yarns is reduced upon contact with the belt and the filaments of the yarns are forced into a folded configuration in which they are then heat set.

Mazzone 1 Dec. 25, 1973 1 1 PROCESS AND APPARATUS FOR TEXTURIZING YARN Charles P. Mazzone, 16 Pine St., Dover, NJ. 07801 [22] Filed: Oct. 13, 1972 [21] Appl. No.: 297,566

Related US. Application Data [63] Continuation-in-part of Ser. No. 266,184, June 26,

1972, abandoned.

[76] Inventor:

[52] US. Cl 28/l.3, 28/1.6, 28/72.], 28/7211 [51] Int. Cl D02g 1/20 [58] Field of Search 28/12, 1.3, 1.6, 28/7214, 72.1, 72.11

[56] References Cited UNlTED STATES PATENTS 2,768,092 10/1956 Lawrence 28/72.]4 X

3,280,440 10/1966 Carruthers 28/7214 X 3,358,344 12/1967 Daniel 28/1.2 3,387,349 6/1968 Trifunovic et a1. 28/7214 X 3,438,101 4/1969 Le Noir et a1. 28/7214 X 3,457,613 7/1969 McClure 28/].2 X

3,528,148 9/1970 Stanley l 28/1.2 3,601,872 8/1971 Potman et a1 28/l.3

3,636,599 l/l972 Stanley 28/1.6

Primary ExaminerLouis K. Rimrodt Att0rneyMichael T. Frimer et a1.

[57] ABSTRACT Multiple ends of continuous multifilament yarns are texturized within a pressure applying zone formed by confronting surfaces of a moving belt and a rotating heated roll with said confronting surfaces moving in the same direction. The yarns are arranged in spaced side-by-side relationship and fed at a speed greater than that of the moving belt into contact with the heated roll at a point upstream from the pressure applying zone, the peripheral speed of the heated roll being at least 1.4 times that of the moving belt. The filaments of the yarns are differentially shrunk and then carried into the pressure applying zone, i.e., between the rotating roll and the moving belt. The surface of the moving belt has a greater gripping power on the multifilament yarns than the heated r011 surface, whereby the speed of the multifilament yarns is reduced upon contact with the belt and the filaments of the yarns are forced into a folded configuration in which they are then heat set.

10 Claims, 2 Drawing Figures PROCESS AND APPARATUS FOR TEXTURIZING YARN The present application is a Continuation-in-Part of application Ser. No. 266,184, filed June 26, 1972.

This invention relates to texturizing continuous multifilament yarn by differentially shrinking the continuous filaments and then setting them in a folded configuration.

Fibrous materials have been texturized by passing them between surfaces which are moving at different speeds. In US. Pat. No. 2,818,630 synthetic fibers are crimped by passing them through the nip between two smooth surface rolls which are driven at different peripheral speeds. The difference in the peripheral speeds produces a rubbing action on the fibers by the-rolls which appears to stretch one side of each filament more than the other, resulting in a crimped product.

British Patent 1,255,957 discloses crimping continuous filaments by passing them between an endless flexible belt and a roll which are in arcuate contact and which are located within a heated liquid medium. The filaments are fed onto a flexible belt and are carried into the area of arcuate contact. The surface speed of the endless belt is different from the peripheral speed of the roll, preferably greater, such as higher. The belt controls the forward speed of the filaments while the roll exerts a compressive and sheering couple on the filaments, causing them to crimp.

In accordance with the present invention, a unique texturized effect is obtained by setting filaments in a folded configuration rather than by differentially stretching them. Multiple ends of continous multifilament thermoplastic yarn are texturized within a pressure applying zone formed by confronting surfaces of a moving, endless belt and a heated roll, with said confronting surfaces moving in the same direction. The

yarns are arranged in spaced, side-by-side relationship and fed at a speed at least 10 percent greater than the speed of the moving belt into contact with the heated roll at a point upstream from the pressure applying zone, the peripheral speed of the heated roll being at least 1.4 times the speed of the belt.

While in contact with the heated roll, but prior to entering the pressure applying zone, the multifilament yarns are differentially shrunk. This is accomplished by controlling the extent of contact of the multifilament yarns with the heated roll so that individual filaments are differentially heated while at the same time maintaining the multifilament yarns under such low tension which permits shrinkage of individual filaments. As a result of differential shrinkage, convolutions or loops are formed in the filaments which are not shrunk or are shrunk to a lesser extent and the individual filaments of the yarn are separated from one another.

The heated roll forces the differentially shrunk yarn into the pressure applying zone at a speed greater than that of the endless belt. The gripping power of the surface of the belt on the yarn is greater than the gripping power of the heated roll. As a result the forward speed of the yarn is reduced by the belt and upon entering the pressure applying zone the individual filaments of the multifilament yarns are forced into a random, folded configuration. The yarns are then heat set in the folded configuration.

The invention will be more readily understood when the following detailed description is read with the accompanying drawings wherein:

FIG. 1 is a schematic, side elevation of an apparatus for carrying out the present invention; and

FIG. 2 schematically illustrates an alternative arrangement of the moving, endless belt and the heated roll.

Referring to FIG. 1, multifilament thermoplastic yarns 3 are unwound side-by-side from beam 2 and conveyed through a comb or reed 5 to feed rolls 4 and 4'. The peripheral speed of the feed rolls 4 and 4' is greater than the speed of the belt 15 so that there is an overfeed of yarns 3 relative to the belt. From the feed rolls, the yarns 3 are fed in spaced side-by-side relation ship to heated roll 7. The yarns are carried over bar 27 into contact with the heated roll at a point upstream from the moving belt 15. The yarns are differentially shrunk in the arcuate portion of roll 7 between the initial point of yarn contact with the heated roll and the initial point of contact with moving belt 15 shown as arrows A and B, respectively.

To obtain differential shrinkage a number of conditions must exist. First, there must be little or no tension on the yarn within the differential shrinkage zone so as to permit shrinkage of the yarns, i.e., the tension must be less than the shrinkage forces of the yarn. Such tension conditions result in the present procedure from the overfeeding of the yarns relative to the moving belt. Additionally, the temperature of the heated roll 7 and the contact time of the multifilament yarns therewith are correlatively controlled so that the individual filaments of the yarn shrink to different extents. As a result of this differential shrinkage, the filaments which do not shrink or shrink to a lesser extent are forced outwards into loops or convolutions, thus spreading out the individual filaments of the yarn.

The differentially shrunk yarns are advanced by the heated roll 7 into the pressure applying zone between the confronting or contacting surfaces of the heated roll and the moving belt 15. The contacting surfaces of the heated roll and the belt move in the same direction. The moving belt 15 is controlled by driven roll 19 and idler rolls l7, l8, and 20 with rolls l7 and 18 pressing the belt against the heated roll. The peripheral speed of the heated roll is at least 1.4 times as fast as the speed of the belt while as discussed above, the peripheral speed of the feed rolls 4 and 4 is at least 10 percent faster than the speed of the belt and thus provides an overfeed in the system relative to the belt. Feed roll 4', heated roll 7 and roll 19 are all positively driven by motor 31 which turns sprocket roll 32 which is provided with multiple sets of sprockets. One end of a sprocket chain 33 passes around sprocket roll 32 while the other end of the sprocket chain passes around sprocket wheel 34 which is connected to feed roll 4'. In a similar manner, heated roll 7 is positively driven by means of sprocket chain 35 which turns sprocket wheel 36 which is connected'to the heated roll. Sprocket chain 37 is driven by sprocket roll 32 and in turn drives gearing mechanism 38 which reverses the direction of revolution. This gearing machanism turns sprocket chain 39, one end of which passes around sprocket wheel 41 connected to roll 19. The relative speeds of feed roll 4', heated roll 7 and roll 19 can be changed by changing the relative sizes of sprocket wheels 34, 36 and 41.

The surface of the belt 15 has a greater gripping power for the yarns than the surface of the heated roll so that the belt controls the speed at which the yarns are forwarded, i.e., the yarn speed is reduced to the speed of the belt. As a result, the heated roll pushes an overfeed or excess of each yarn onto the belt and the yarn filaments are forced into a random folded configuration on the belt. The filaments are held in this folded configuration during their passage between the heated 1 roll 7 and the belt 15 while being held in contact with the arcuate portion of the heated roll between points B and C, and are heat set into this configuration. After leaving the belt 15, the yarns 3 are cooled in a cooling zone 22 and moved by pull rolls 24 and 24 to winding package 26.

FIG. 2 illustrates an alternative arrangement of the moving, endless belt 15 and the heated roll 7 in which the yarns 3 only contact a very small portion of the heated roll periphery. In this arrangement the yarns are forced into a folded configuration in the pressure applying zone or nip between the heated roll 7 and the belt 15 and then are carried out of contact with the heated roll. Since the yarns 3 are in contact with the heated roll 7 for a very limited period after being forced into a folded configuration, the heated roll heat sets the yarns in this configuration for only a short time. If desired, heat setting can be continued on the belt by means of an additional heat source, such as heater 42, positioned downstream from the nip between heated roll 7 and belt 15. It is necessary to maintain the yarns 3 under little or no tension while they are being heat set on belt 15 so that the folded configuration is not pulled out prior to completion of the heat setting. One or more additional rolls such as idler roll 43 can be used to guide the belt 15 in the path shown in FIG. 2.

The multifilament yarns textured by the present invention contain continuous filaments which can be made of a wide variety of thermoplastic polymers. Examples ofa few of the many suitable polymers are polyamides such as poly(hexamethylene adipamide) and polycaprolactam; polyesters such as polyethylene glycol teraphthalate; polyolefins such as polyethylene and polypropylene; polyurethane and cellulose acetate. Multiple ends of the yarn can be fed from a beam or can be supplied from separate packages mounted on a creel with the yarns being brought into side-by-side relationship by means of conventional guides.

The multifilament yarns are fed from the yarn supply into contact with heated roll 7 at a speed which is at least 10 percent faster than the speed of belt and preferably, the feeding speed is from about 1.2 to four times the speed of the belt. The overfeed relative to the belt is necessary in order to provide the excess yarn required for the folded configuration imparted to the filaments of the yarn. Additionally, as a result of this overfeed, the yarn in contact with the heated roll upstream from the pressure applying zone is under little or no tension and can, therefore, shrink.

As previously indicated, the multifilament yarns are carried into contact with the heated roll 7 at a point upstream from the pressure applying zone formed by the confronting surfaces of the heated roll and the belt 15 and the multifilament yarns are differentially shrunk by the heated roll (i.e., individual filaments of each yarn shrink to different extents) prior to entering the pressure applying zone. As a multifilament yarn is passed over the heated roll, one side of the yarn is in direct contact with the roll and consequently filaments on this side are heated to a greater extent than filaments on the other side. Differential shrinkage is obtained when the time of contact of the multifilament yarn with the heated roll and the temperature of the roll are correlatively controlled so that there is substantial shrinkage of filaments in direct contact with the heated roll while there is little or no shrinkage of other filaments. As a result of differential shrinkage the filaments which do not shrink, or shrink to a lesser extent, are forced outward into loops. This opening up of the yarn prior to crimping has a substantial effect on the final texturized product.

The heat treatment to effect differential shrinkage is quite different from the heating procedure described in the above-mentioned British Patent No. 1,255,957. In the British patent heating is carried out in a liquid bath which would give uniform heating of the filaments and thus no differential shrinkage.

The heat of the heated roll is also utilized to heat set the multifilament yarns. Heat setting to set the yarns in a folded configuration must be carried out at a temperature higher than that encountered in subsequent process steps. Since conventional processing includes exposure to boiling water, the yarn must be heat set at a temperature greater than 212F. To accomplish this, the temperature of the heated roll should be at least 220F. and preferably 250 to 450F.

The peripheral speed of the heater roll 7 is greater than the yarn speed from the yarn supply and is at least 1.4 times, preferably 1.5 to 20 times the speed of the moving belt. The heated roll feeds the yarns into contact with belt 15 which is pressed against the heated roll by roll 17 to form the pressure applying zone. The gripping power of the belt surface on the yarns is greater than that of the heated roll and the yarns are carried through the pressure applying zone at the speed of the belt. As the belt reduces the forward speed of the yarns the filaments are folded into a random configuration. The pressure at the nip formed where roll 17 presses belt 15 against heated roll 7 is generally maintained at from about 10 to lbs. per linear inch, preferably from about 20 to 60 lbs. per linear inch, although higher and lower pressures can be used.

The gripping powers for the yarn of the heated roll and the belt depend upon the materials and structures of the surfaces of the roll and belt. A wide variety of different materials and constructions can be used to obtain the desired relationship of gripping powers. A typical example is a heated metal roll having a matte finish on its surface used in combination with a belt of cotton or polyester fabric. While the gripping power of the heated roll surface must be less than that of the belt, it must be sufficient to enable the heated roll to force the yarn into the nip between the heated roll and the belt. In practice it has been found that smooth surfaces of materials such as metal give noticeable crimping, but that better results are obtained when the roll surface is roughened or engraved.

After being heat set, the yarns are cooled, with care being taken not to pull the filaments out of their folded configuration before they have been cooled. Cooling may be carried out by exposure to air at room temperature. Additional cooling means such as cold rolls and jets of cold air may also be used.

The following example is give to further illustrate the invention.

EXAMPLE l A number of runs were made to texturize denier,

34 filament drawn polyester yarn using an apparatus such as shown in F IG. 1 except that the yarns were supplied from separate packages mounted in a creel and brought into side-by-side relationship by conventional guides. The rolls of the apparatus were 21 inches wide. During the runs the speed of the belt was 23 yards per minute, the temperature of the heated roll was maintained at about 350 to 360F. and 588 yarns spaced at 31 yarns per inch were fed through the apparatus. The pressure at the nip where roll 17 presses belt against heated roll 7 was maintained at about lbs. per linear inch. The speeds of the feed rolls 4 and 4' and the heated roll 7 were varied as shown in the table below. The percent bulk extensions under a 50 gram load were determined for the products before and after heat treatment and are given in the table below. The bulk extensions before heat treatment were measured on yarn samples taken from the end of the cooling zone while the bulk extensions after heat treatment were measured on yarn samples which had been removed from the winding package and heated at 300F. for 5 minutes in a tensionless state. it was noted that before texturizing, the yarn does not extend.

TABLE 1 Speed Speed of Feed of Heated Rolls Roll Percent Bulk Extensions Yards Per Yards Per Before Heat After Heat Minute Minute Treatment Treatment 27 33.1 29.5 53 5 30 62.5 5 36 70 9 36 75.7 14 21 43.3 89.7 28 30 Fabrics knitted from the texturized yarns had a softer hand, better cover and increased elasticity as compared to fabrics knitted from the same yarn without texturizing. These effects were greater in the fabrics prepared from the yarns having the higher bulk extensions.

When yarns were run through the apparatus without overfeeding there was no texturizing effect on the yarn.

EXAMPLE 2 The yarn used in Example 1 was textured employing the same apparatus except that the heated roll 7 and the moving belt 15 were arranged as shown in FIG. 2. The heater 42 was not utilized. Heated roll 7 was maintained at 380 to 390F. and 588 yarns spaced at 31 yarns per inch were fed through the apparatus. The speeds of the belt 15, the feed rolls 4 and 4 and the heated roll 7 are shown in the Table below. Also shown in the Table are the bulk extensions after heat treatment, which were measured in accordance with the procedure described in Example 1.

TABLE 2 Speed Speed of Feed of Heated Speed I Rolls Roll of Belt Percent Bulk Yards Per Yards Per Yards Per Extension After Minutc Minute Minute Heat Treatment 39.0 117.6 16.1 63 34.6 127.0 10.3 66

It will be apparent that many modifications and variations can be effected without departing from the scope of the novel concepts of the present invention, and the illustrative details disclosed are not to be construed as imposing undue limitations on the invention.

I claim:

1. A process for texturizing multiple ends of continuous multifilament thermoplastic yarns within a pressure applying zone formed by confronting surfaces of a moving belt and a rotating heated roll, with the confronting surfaces moving in the same direction, said process comprising; feeding a plurality of multifilament yarns arranged in spaced side-by-side relationship into contact with said heated roll at a point upstream from said pressure applying zone at a speed at least 10 percent greater than the speed of said moving belt while maintaining said multifilament yarns under a tension which permits shrinkage of individual filaments and correlatively controlling the extent of contact of the multifilament yarns with the heated roll and the temperature of the heated roll so that differential shrinkage of the multifilament yarns takes place prior to entering said pressure applying zone; thereafter advancing said multifilament yarns into said pressure applying zone between said confronting surfaces, the peripheral speed of said heated roll being greater than both the feeding speed and the speed of said moving belt and the gripping power of the belt surface on the multifilament yarns being greater than that of the heated roll surface whereby the speed of said multifilament yarns is reduced upon contact with said belt and the filaments of said multifilament yarns are forced into a folded configuration; heat setting said yarn filaments in said folded configuration and feeding the heat set yarn into a cooling zone.

2. A process as claimed in claim 1 wherein said multifilament yarns are fed into contact with said heated roll at a speed equal to about 1.2 to four times the speed of said moving belt.

3. A process as claimed in claim 1 wherein the peripheral speed of said heated roll is at least 1.4 times the speed of said moving belt.

4. A process as claimed in claim 1 wherein the peripheral speed of said heated roll is from about 1.5 to 20 times the speed of said moving belt.

5. A process as claimed in claim 1 wherein the multifilament yarns are heated to a temperature greater than 212F. during said heat setting.

6. A process as claimed in claim 5 wherein the heated roll is maintained at a temperature of about 250 to 450F.

7. A process as claimed in claim 1 wherein said yarn filaments are heat set while held between said moving belt and said rotating heated roll.

8. A process as claimed in claim 7 wherein said yarn filaments are further heat set on said moving belt after being carried out of contact with said rotating heated roll.

9. An apparatus for texturizing multiple ends of continuous multifilament thermoplastic yarns within a pressure applying zone formed by confronting surfaces of a moving belt and a rotating heated roll, said apparatus comprising a heated rotatable roll; means for feeding said multifilament yarns in spaced side-by-side relationship from a yarn supply into contact with said heated roll at a controlled feeding speed; an endless flexible belt urged into contact with the peripheral surface of the heated roll at a location downstream from the initial points of contact of said yarns with said heated roll to form a pressure applying zone through which said yarns are moved, the surface of said flexible belt having a greater gripping power for said yarns than the speed of the belt and the filaments of the multifilament yarn are forced into a folded configuration and means to heat said filaments while in said folded configuration to heat set the filaments in this configuration. 10. An apparatus as claimed in claim 9 wherein said multifilament yarns are contacted with a cooling means after being heat set.

' UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 780,404 Dated December 25, 1973 lnvent fl Charles P. Mazzone It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the first page, in the first column of the patent, under "Inventor:" should appear Assignee: J. P. Stevens & Co.,Inc. New York; N. Y.

Signed and sealed this 7th day of May 1971+.

(SEAL) Atte st:

EDWARD IF'LMLETCHERNTIL C. MARSHALL DANN I Attesting Officer 7 Commissioner of Patents 

1. A process for texturizing multiple ends of continuous multifilament thermoplastic yarns within a pressure applying zone formed by confronting surfaces of a moving belt and a rotating heated roll, with the confronting surfaces moving in the same direction, said process comprising; feeding a plurality of multifilament yarns arranged in spaced side-by-side relationship into contact with said heated roll at a point upstream from said pressure applying zone at a speed at least 10 percent greater than the speed of said moving belt while maintaining said multifilament yarns under a tension which Permits shrinkage of individual filaments and correlatively controlling the extent of contact of the multifilament yarns with the heated roll and the temperature of the heated roll so that differential shrinkage of the multifilament yarns takes place prior to entering said pressure applying zone; thereafter advancing said multifilament yarns into said pressure applying zone between said confronting surfaces, the peripheral speed of said heated roll being greater than both the feeding speed and the speed of said moving belt and the gripping power of the belt surface on the multifilament yarns being greater than that of the heated roll surface whereby the speed of said multifilament yarns is reduced upon contact with said belt and the filaments of said multifilament yarns are forced into a folded configuration; heat setting said yarn filaments in said folded configuration and feeding the heat set yarn into a cooling zone.
 2. A process as claimed in claim 1 wherein said multifilament yarns are fed into contact with said heated roll at a speed equal to about 1.2 to four times the speed of said moving belt.
 3. A process as claimed in claim 1 wherein the peripheral speed of said heated roll is at least 1.4 times the speed of said moving belt.
 4. A process as claimed in claim 1 wherein the peripheral speed of said heated roll is from about 1.5 to 20 times the speed of said moving belt.
 5. A process as claimed in claim 1 wherein the multifilament yarns are heated to a temperature greater than 212*F. during said heat setting.
 6. A process as claimed in claim 5 wherein the heated roll is maintained at a temperature of about 250* to 450*F.
 7. A process as claimed in claim 1 wherein said yarn filaments are heat set while held between said moving belt and said rotating heated roll.
 8. A process as claimed in claim 7 wherein said yarn filaments are further heat set on said moving belt after being carried out of contact with said rotating heated roll.
 9. An apparatus for texturizing multiple ends of continuous multifilament thermoplastic yarns within a pressure applying zone formed by confronting surfaces of a moving belt and a rotating heated roll, said apparatus comprising a heated rotatable roll; means for feeding said multifilament yarns in spaced side-by-side relationship from a yarn supply into contact with said heated roll at a controlled feeding speed; an endless flexible belt urged into contact with the peripheral surface of the heated roll at a location downstream from the initial points of contact of said yarns with said heated roll to form a pressure applying zone through which said yarns are moved, the surface of said flexible belt having a greater gripping power for said yarns than said heated roll to permit said belt to control the speed of the yarns through said pressure applying zone; means to drive said heated roll, said belt and said feeding means so that the peripheral speed of said heated roll is greater than said controlled feeding speed and at least 1.4 times the speed of the belt, and the controlled feeding speed is at least 10 percent greater than the speed of said belt whereby said multifilament yarns are fed into contact with said belt at a speed greater than the speed of the belt and the filaments of the multifilament yarn are forced into a folded configuration and means to heat said filaments while in said folded configuration to heat set the filaments in this configuration.
 10. An apparatus as claimed in claim 9 wherein said multifilament yarns are contacted with a cooling means after being heat set. 